The present invention generally relates to power regulation systems for microelectronic devices such as microprocessors. More particularly, the invention relates to devices for producing a load current across a power regulation system that emulates transient power demands or spikes produced by a microelectronic device and to systems including the device.
As the speed and integration of microelectronic circuits such as microprocessors increase, the speed and current of the power required to operate the circuits generally increases. The increased current load at higher speeds often results in severe current transients in the power delivery system. The current transients, if not regulated or accounted for, can cause noise on the power supply, which in turn may induce errors on the microprocessor. Accordingly, it is desirable to design power supply systems that are able to regulate transient current events.
Simulation modeling is often used to design power supply systems and predict the performance of the systems, often prior to completion of the design of the microprocessor. Although modeling of the power supply systems facilitates design of the system, modeling generally cannot account for all variables that contribute to generating power transients. In addition, even when simulation modeling is employed to design power systems, final testing of the power supply systems, particularly under severe dynamic transient conditions, typically requires coupling a power regulation system to a microprocessor and operating the microprocessor, and thus requires that the design of the microprocessor be complete. Because the testing is performed after final design of the microprocessor, any desired changes to the microprocessor and/or the power delivery system are difficult and costly. In addition, testing the operating conditions of the power delivery system while operating the microprocessor may make it difficult to determine the source of any power supply or demand irregularities. Accordingly, improved methods and apparatus for testing the performance of a microelectronic power supply are desired.
The present invention provides an apparatus for testing microelectronic power regulation systems. More particularly, the invention provides a circuit for producing power which emulates transient power events that might occur during operation of a microelectronic device such as a microprocessor. In addition, the invention facilitates design optimization or improvement of the power delivery system by allowing testing of the systems without requiring final design of the microprocessors for which the systems will be used.
In accordance with one embodiment of the invention, a transient load generator includes a control circuit and a transistor configured to turn on and off to emulate a transient power event.
In accordance with one embodiment of the present invention, a transient load generator includes a first output voltage source, a second output voltage source, a first current source coupled to the second voltage source, a second current source coupled to the second voltage source, a control circuit coupled to the second current source, a first transistor having a having a base region coupled to the first current source and a collector region coupled to the first output voltage source, and a second transistor having a base coupled to the second current source, and an emitter region coupled to the base region of the first emitter. The generator may also include additional components such as resistors and diodes to facilitate formation of power spikes that emulate transient events produced by a microprocessor.
In accordance with another embodiment of the invention, a transient load generator includes a first voltage source, a second voltage source, a control circuit, a first current source coupled to control circuit and the second voltage source, a first transistor having a gate region coupled to the current source, a source region tied to ground, and a drain region tied to the first voltage source; and a second transistor having a gate region and a drain region tied to the current source, and a source region tied to ground.
In accordance with another embodiment of the invention, an assembly includes a substrate, one or more transient load generators coupled to a portion of the substrate, and may also include one or more secondary power regulators and/or decoupling capacitors coupled to additional portions of the substrate.